1. Field of the Invention
The present invention relates to a light source module comprising a light source, which light source is connected by a light source base, which light source module comprises cooling means for cooling the light source base, which light source module further comprises a dichroic reflector, where at least one heat sink surrounds the dichroic reflector.
2. Description of Related Art
Reducing the pinch temperature of a light source base at least with lamps having a filament is very important. The filament is connected by electric conductive means through the lamp closure and through the lamp base. Increasing temperature leads to an oxidation and corrosion of the electric conductors. This leads to a reduction of the lifetime of the lamp. Therefore, the temperature at the pitch must typically be reduced to a temperature below 450-500 degrees C.
U.S. Pat. No. 5,626,416 describes a lamp module apparatus comprising a reflector where a fan generates an air stream. The air stream surrounds a lamp base before the air stream splits up and continues into a space between an inner reflector and the lamp where another part of the air stream flows between the inner and an outer reflector. Infrared light generated by the lamp passes through the inner reflector towards the outer reflector where infrared light is partly absorbed and partly reflected.
A part of the infrared light that is absorbed in the outer reflector is radiated again at lower frequencies and partly towards the lamp base. Hereby, the lamp base might be heated to a temperature which is so high that it reduces the lifetime of the lamp.
U.S. Pat. No. 5,515,245 describes a light source housing which contains a light source where heat removal is provided by cooling fins and a heat filter supported in the light path, and where a portion of the light is reflected towards the cooling fins.
The cooling fins surround the reflector, but infrared light passes through the reflector, and is absorbed in the cooling fins. At least some of the cooling fins conduct the absorbed heat towards the lamp base, which leads to an increase of the temperature in the lamp base. This can lead to a reduced lifetime of the lamp.
U.S. Pat. No. 6,817,737 B2 describes a light projector which includes an elliptical reflector, a first spherical retro-reflector, the first retro-reflector having an first aperture formed therein, the first aperture having a first diameter and a first center-point, a second spherical retro-reflector located between the elliptical reflector and the first retro-reflector, the second retro-reflector having a second aperture formed therein, the second aperture having a second diameter and a second center-point, the second diameter smaller than the first diameter, the first and second center-points lying along a common axis, and a light source, the light source located at a foci of the elliptical reflector, the light source lying along the common axis, the elliptical reflector reflecting light emitted by the light source, the reflected light passing through the first and second apertures, the first and second retro-reflectors being positioned so as to reflect light emitted by the light source back towards the light source. Also provided is a light projector that includes a light source projecting a beam of light; and an optical element movable between a first position in which the beam of light does not impinge upon the optical element, a second position in which substantially all of the beam of light impinges upon the optical element, and a plurality of intermediate positions in which a portion of the beam of light impinges upon the optical element, wherein the optical element is comprised of a plurality of radially sectioned sub-elements.
This patent application describes cooling fins, which cooling fins are connected mechanical towards the reflector, and which cooling fins surrounds the reflector. No air gap is present between the reflector and the cooling fins. Thereby no airflow is possible between the reflector and the cooling fins. Only limited convection air-cooling takes place between the dishes.